Just tried this on the run Bristol - Bath at a low 76/72 psi - improved by 6 mins over 14 miles - on a heavier bike! Much more comfortable as well, revelatory.
Very good. Another factor to consider is temperature, for instance, filling to optimal pressure while indoors at 20C or 70F and then going outside into 5C or 40F or beginning with 70F but going out on a hot day into 90F
I believe the Silca Tire Pressure calculator may be the best- as it factors in road conditions, total system weight, tire type and average speed. It is also important to ensure your tire gauge is accurate and that the hose is properly inserted on to the valve- otherwise you may fall well below or possibly above the recommended pressures.
Speaking of real world. So many stop signs mean I never hit 40 kmh. Used SRAM calculator like he said and noticed immediate improvement on speed. 11 kmh to 20. I was running 38 PSI and the change to 70 PSI did wonders.
Regarding the different results some people get between the Sram and Silca calculators, it's important to actually physically measure your mounted tyre width for the silca calculator! You don't need to with the sram calculator as it takes into account the inner rim width! I get nearly the same results from both calculators when i enter the details correctly! In the Sram i enter 32mm tyre width and 25mm internal rim width. In the Silca i enter 34mm as thats what my tyres measure at when fitted! If i enter them as 32mm (labeled width) the pressure recommendation goes up 6+psi. For my tt bike with 25mm tyres and tubes, when i enter the details (these tyres measure at 25mm when fitted too) the results from both are about the same.
It's funny, but I have no idea what tire pressure I run. I have a 40 year old Silca track pump, and the pressure gauge has been broken for a number of years. I've just been pumping up my tires and using my thumb to check the tire to see if it feels ok, and that's been working out very well for me. It's all about the feel. I'm old school 😆😁
I had been using the Silca tire pressure calculator. With that calculator, I get a 16 PSI higher tire pressure than if I use the SRAM calculator with the same parameters. That's a lot!
With the silca one, you need to input the actual measured tyre width when mounted, not what is written on it! And there's a lot more options on the road surface to select. For example, in the stream calculator I enter 32mm tyres, 25mm internal rim, and road surface, and get pressures of 57.9 and 54.5 Using the silca calculator I select worn pavement/some cracks, 34mm (as this is what my tyres mounted measure at) and get 58.5 and 57. Pretty close! If I change my the width to 32mm (as written on the side) then the silca recommended pressures go up by 6psi! So it's key with the silca calculator to measure the tyres width when fitted!
I just replaced a slow leaking tube that would drop from 55 psi to 35 psi over the span of about 5 days/rides. Personally, the rides at the beginning of the inflation cycle felt slightly easier on the legs but I can't detect subtle changes of effort because all I have is dumb MPH. I think I'm going to start out the new tube at 45 psi and see where that gets me.
Nice video, and glad you got the the 'how' part. For myself, I do it old school - based on the width of the tire, determining contact patch, and based on my weight. And as I am not pumping my tires up to some tenth of a pound, it is very fair. Also, not at all far off from the web based calculation.
Thanks for the answer man! :) Does your fork allow for 35 mm? My road bike has an approximated inner fork width of 34 mm. (I measured it but it's a bit tricky...) I even hope that an inflated 32 mm tire won't expand more than 2 mm or I'm a bit screwed...😅
@@nerdexproject Yeah my fork allow 35mm in datasheets, so i could go a bit wider too. I think its not good idea to put 32mm tire to 34mm fork, you shou have +/-5mm reserve on each side. The wheel bends quite a lot while cornering :)
You're ruining my internet fun by providing such a nuanced and well explained video! I was so very ready to jump into the comments calling out nuances you missed. 🤣 Great work!
brilliant thanks very interesting will continue with my own tweeking on various bikes ....work bike needs lower pressure still for sure, road bike still lowering pressure gradually to get used to the feel... and hack bike is a cross bread so going to put wider tyres on that soon too, particularly for the wet conditions.... hard tail stays the same for now in case of snow or floods ha ha ha thanks again for the study..... sorry to here of the changes to GCN + will certainly continue to follow here, have indulged in new bib tights and jersey from your shop too hope the sales help keep the original idea afloat amid the new fangled streaming stuff ha ha ha thanks to your whole team enjoy your winter looking very gnarly ..Cheers Martin
Hey Michael, it’s a super important topic and we want to make sure that we’re creating videos for all cyclists not just the ones who’ve been watching GCN for a while. I’m afraid not every video can be relevant to every person, and if you already knew everything in this one hopefully there’ll be another video for you along soon. Cheers, Simon
lower preasure means less chances for your inner tube to blow up. im 120kg and having high presure on a hot day is like asking for a road side replacement job :D
I’ve always pumped mine up to where they deform enough to smooth out the crappy English roads but enough to corner hard and it’s usuall at least 20 psi than the max recommended.
You could hear the hurt and disappoinent (of the GCN+ cancellation) in Si's voice in his last sentence 😢. We are extremely disappointed but you guys must be gutted...❤
I've been trying to get this across to people for over a decade. I typically had to order tires because the selection of 25 & 28mm performance tires were never in stock. I had to check my pressures right before heading to the line because I had a friend who would go behind my back and pump my tires to the max before races stating I was loosing watts.
I have noticed that after after adopting this lowering tire pressure trend my body can take more cycling before feeling aches. But I have suffered a lot of sidewall tearing in many of my continental tires... You win some, lose some I guess.
I still cannot get used to lower pressures when you nail it out the saddle and you feel your tyre squishing it feels horrid. That's at 80 psi. I am a heavier rider. 120 psi for me
Really great info. I, like I think many others, started off cycling with 120psi in the rear tire and 110 in the front. Those were some painful days. I had lowered that pressure quite a bit, but according to the calculator, not nearly enough. Really looking forward to setting them at the recommended pressures and seeing how it feels. I'm always up for a little more comfort and some added speed for free. Thanks for the really well done video Si.
I personally would not recommend that. Go at least 10 psi higher than the calculator. My rear inner tube got a 1/8" long split most probably because of bad contact with the rim when I had set it to the recommended pressure from that calculator. Got thrown over the bars on a 25mph downhill descent. Nothing wrong with the tire/rim or any sharp stuff stuck inside. This is just my experience and opinion. Never had such an incident when running higher pressures. (Or the manufacturer recommended pressures)
@@padmanabhaprasannasimha5385 I've been running the recommended pressures for the past two rides and there is a notable difference in comfort on the bike. Really nice. I don't feel every little nook and cranny in the road as I did at the higher pressures. But to each their own, you have to do what makes you feel safe.
I just use 100psi (on my road-bike) and be done with it. On my “cross-country”-type mountain-bike some local-bike-shops have put-in 40psi and some others have put-in 45psi and some-others have e put-in 50psi and some-others have put-in 60psi. Why the different variances? I dunno. But my tyres say “withstands up-to a MAXIMUM of 65psi” so i hypothesize that all-those-pressures that the local-bike-shops out-in are okay. (Also: the bike felt comfortable-to-ride with each of those pressures in the tyres, *AND*, i didn’t get impact-flats with any of those pressures).
I still think slimmer is faster! Faster climbing and accelerating anyway, because they're lighter. Now we have tubeless you can simply run skinnier tyres at lower pressures!
For me it is suggest too low pressure, so the tier getting spoungy. 11 kg bike, 700x35c, 17 mm rim. Max load on the tier 6 bar. The calculator suggest just under 4 bar. I go for 5 bar.
I’m disturbed to find Si saying lateral cornering pressures is so incredibly soothing. Anyway, back on the topic, SRAM is my go to calculator as well. I’m also nerdy enough to have a digital pressure gauge. I’d like to think I’m not obsessive just ensuring a nice ride
The digital gauge is not that nerdy after all. If you have an old school pump that goes up to 12 bar and you want to set your MTB tires to 1.6 and 1.8, it‘s almost impossible without it. One of my best gear buys.
29mm tire, thin good pavement - 5-5.3 bar- This works, however I have a question, why tire manufactures suggest higher pressure? even minimum more like 6 bar. You have Pirelli tires, look at the table on a box. Pirelli suggests >6 bar for that setup....
Wish there was something like TyreWiz with +/-5PSI accuracy, for a sensible price. All I want to know is "have I lost more than 10PSI since I pumped up at the start of the ride?". Especially important on Tubeless setups.
I kept running the hookless recommendation of 60-65 PSI even after I switched back to hooked wheels on accident, lol Silca says I should be at 90 PSI -- we're gonna take that with a grain of salt.
On my TT bike, with 25mm tyres and tubes they both suggest about 95psi. That's about the right mark. On my road bike with tubeless 32's they have me at 57 and 54. Down to 49 even in the wet.
@@MrWobling but I just moved from the other lbs that told me my rear cassette needed new bearings 😂...but seriously I'm on my 3rd lbs and the latest crew seem really good
Using the SRAM website and input all data correctly of my mtb i find that tyre pressure of 25 psi is recommended! Now thats way below what's stamped as minimum on my tyres 35 psi - thoughts GCN ?
After Si‘s musical performance in the latest GCN show, I was a bit disappointed that there is no Freddie Mercury reenactment in this video after seeing the title.
@malmsey1541 Not on clinchers. Of course it also could depend on how you measure your tire pressure. With my tires and pressure gauge it is pretty close to ideal. I usually go about 2 psi lower than what the calculator says. But is my digital gauge even accurate to +/- 2 psi? I have no idea. Certainly the ones on floor pumps aren't.
I often wonder why it is not told that the Bicycle Rolling Resistance tests are done on an uneven surface that corresponds to natural conditions?? The result is that more pressure is faster on a normal surface??
excellent video as usual. I am going to keep my new road bike's 28mm tyres until they last long enough, but once they are done, I'm switching to 32mm tyres (the max my bike accepts). My two pump's gauges aren''t working well though, so I might have to buy something to read the pressure accurately.
A separate digital pressure gauge is really worth it. I use mine before every ride and also take it with me to races and set my pressure in the hotel room with a hand pump.
Sometimes it is mental. When I lower my wifes tires to 70 because she is 135 pounds on a 25 pound bike, she does the ride in 4 hours instead of 3. Pump back to 85 (max for her tires) she does 3 hours (same distance of course). My next move is drop to 70 and not tell her as a test lol.
Your Sram tyre pressure calculator has no TPU tubes option! Shame! Well, I use TPU inners last 2 years and max pressure recommended is 75psi. That's it. I'm 125kg and I run TPU inners RideNow. Previously I had butyl inners and 115psi - nightmare. If I follow your calculator I should run 122psi. 😂😂. I do perfectly well with 75psi with no flats and no problems. It's perfect. You guys should tell the people how different tyre setup works. Does matter if you run TPU, butyl, latex or tubeless. Another thing. Tyre pressure is changing with the speed, temperature, breaking (rims), loading etc. and varies during the ride. 2psi diffece for recreational ride is nothing. I haven't found your video useful this time. I'm sorry. By the way TPU inners are much better for road bikes. Cheaper, lighter and faster than the tubeless. 👍
I ran the calculator at 125kg, and to get a 122psi recommendation, I had to select 23mm tires on a 15mm rim - a very old school set-up. Nothing against old school set-ups, but it seems odd to run this with modern TPUs. I don't doubt your experience running 75psi without pinch flats, but am wondering if everything was entered into the calculator correctly?
@@andrewmcalister3462As per the RideNow TPU manual, the maximum pressure must be 75psi. It's not recommended to put more pressure than this. This is why I'm doing it and everything is perfect. The app recommended in the video above - Sram pressure calculator has NO TPU inner tubes option. Their calculations are for butyl or latex tubes only which doesn't make any sense. Driving on Lower pressure completely chenging the game as we know and all the other options, inclusive tubeless are useless for road bikes. I don't think tubeless is better for road bikes at all. The sealing is less and doesn't work as effective as with the MTB/gravels, but the mess is huge, it's expensive (wheels, tyres, valves, pumps, repair kit etc). TPU are 21-36g each and the repair kit is a self adhesive patch and a small alcohol wipe or 1g total. You need a basic pump and that's it. I wonder why GCN and Sram don't promote the TPU tubes? May be they want us to spend more money for a premium gear?
Hi Si, I just purchased a new set of Zipp 303 Firecrest hookless rims for a Cervelo Soloist. Living in Colorado USA was looking for an all around wheelset (replacing Reserve 40/44 76/176 hub) primarily for paved road riding, on flats & rollers, with an occasional off road / hard packed dirt farm road. I plan on following Zipp’s compliance standards (Less than 73 psi, tires greater than 28mm, & following the hookless tire compatibility. Question: 1) Following De Gendt’s crash and the UCI’s investigation into the safety of hookless; what has been your experience with riding & racing hookless tires on paved & hard pack dirt roads, any tires blowing off the rims. And 2) Could you rank the following tires 30mm: Sworks Turbo 2BR 2T/5T, Schwalbe Pro One TLE and GP 5000 AS TR. As a newbie to hookless rims I’m trying to determine if this is the right move. Thanks for all you do
A little late now, but investigation showed that De Gendt was riding a 28 mm tyre when the minimum recommended was 30. That's almost certainly the reason for the bow out. I've had the same wheels for about a month and no problems even descending at speed down passes. Follow Zipp's recommendations for compatible tyre/pressure combinations.
110psi on Pirelli P Zero….I weigh ~210lbs. SRAM says I should be running at ~90. I used to ride Conti’s. Their box recommends 110 for my weight. Who’s correct?
I thought I had my tyre pressures nicely dialed in but it turns out I was running at 60psi (40mm tyres on a touring bike) when I should have been running 40psi when fully loaded. Only 35psi when not touring with no luggage. Very surprising!! Thanks Si.
I don't really care because I can google it, but I found no link to the tire pressure calculator in the description... unless it's very well hidden amongst the advertising links.
My road bike with 32mm tubeless, 57 and 54 (pretty much the same results from both calculators). Sram recommends 53 and 49 in the wet. I'm wondering if i could run that all the time? I wanna run as low as i can without making me slower. Comfort is king for me! On my TT bike i run about 90psi, which is a little under what both calculators recommend.
The calculated pressure is well below what pirelli recommends, about 1.5 bar difference for 26 mm, also using the silca tool results in higer pressure by 0.5 bar. So not sure what is optimal. HOWEVER, the 5.5 bar in 26 mm feels so soft compared to the 6.5 bar I usually run.
But Silva also describes how a slightly lower pressure affects losses only slightly, while being above the sweet spot increases mentioned losses comparably drastic. So I think being between the SRAM and Silva calculator is not a bad idea. :)
Off topic, but, it’s really great canyon are sponsoring GCN and all and giving them all these flashy bikes, but it’s kinda annoying that after seeing all these cool colours, when I go on their website everything I’d be interested in seems to still be shades of beige 🤣
The tire has defective, the thickness of tire is varies from part to part. I'm 78kg weight with 25mm tubular, so I put it in the front 65 and the back 75 psi. This is 10 psi lower than the recommended air pressure of the slam.
I accept the science but what I'd like to know is how much actual difference does it make to the average cyclist in real world scenarios? For example, if the pressure calculator says I should run 75psi on my rear tyre but it's at 95psi exactly how slower will it be? Over a 30 mile ride is it minutes or just seconds?
60psi front and rear on 700x30 Schwalbe pro one running tubeless, I weigh around 72/74 kg depending on when I weigh myself! Btw the roads where I ride are awful.
Does anyone happen to know of Conti GP5000 clincher and the S TR version are standard or reinforced? I'm not sure where to find this information. Thanks in advance.
You got one thing wrong. Air volume is what is holding up the weight. Therefore the more air in the tire the less pressure the air needs to be under to support a given weight.
Wrong. What's supporting the weight is the internal pressure (pounds per square inch) times the area of the contact patch (square inches). The resulting force, in pounds, is what is supporting the weight of the bike.
@@mikes1976 Now that is funny, Mike S. arguing with Mike S. lol. However, if you think that the entire volume of air is not contributing to holding up the weight then you are mistaken. Yes, the area of contact is the point at which the balancing force is concentrated. But every atom of atmosphere in the system is contributing to that balancing force. If the volume of the system is smaller then each atom has to contribute more force and therefore they need to be at a higher pressure.
Is it cynical of me to think these calculators are skewed to lower pressures to help sell Zipp's hookless rims? I looked at the white paper and it seemed biased to me. They didn't present data on new or good condition asphalt, and "rough" was not defined by anything more specific than rough.
Hey Greg, we asked Zipp this exact question and they pointed out that their tyre pressure research proceeded hookless. They made the move to hookless when they realised that high pressures weren’t needed.
It's very informative for people who race for instance. But for the majority of us it doesn't matter. On my summer bike I put 80 psi in the front and 85 in the back. On my hybrid winter bike I put 30 psi for off road and 40 psi for the road. No faffing about. People are whittling about too much technology, just get out and ride your bloody BIKE😊
Just checked SRAM's calculator. I ride Pirelli P Zero Race tubeless tires with the new Speedcore feature at 28mm. Would this tire be considered thin, standard or reinforced?
Am I correct in assuming that the calculator is for tubeless tires only? It doesn’t say that but the pressures Si is showing seem appropriate for tubeless but not tubed.
Yes some brands like Schwalbe have recommended pressure range quite high. Usually I'm running tires around the lower limit but not too much lower, make sure it does not feel too soft when cornering.
What tyre pressure do you run? 🛞
65
10
Well below the tire pressures given by Silca. I use SRAM pressure calculator which takes into account the fact I'm running tubeless on crap roads.
120psi
75-80 psi
Just tried this on the run Bristol - Bath at a low 76/72 psi - improved by 6 mins over 14 miles - on a heavier bike! Much more comfortable as well, revelatory.
Very good. Another factor to consider is temperature, for instance, filling to optimal pressure while indoors at 20C or 70F and then going outside into 5C or 40F or beginning with 70F but going out on a hot day into 90F
Civilized people use Centigrade.
@@zygmuntthecacaokakistocrat6589 And smart, civilised people use Celsius as Centigrade is outdated nomenclature. 😜
@@zygmuntthecacaokakistocrat6589 And the really intelligent people of this world (aka scientists) use Kelvin, K.
😊
And as pressure is proportional to temperature in Kelvin , there will only be a small percentage change going from 293 K to 278 K.
lick your finger and put out of the window, this way you also check wind power and direction .
I believe the Silca Tire Pressure calculator may be the best- as it factors in road conditions, total system weight, tire type and average speed. It is also important to ensure your tire gauge is accurate and that the hose is properly inserted on to the valve- otherwise you may fall well below or possibly above the recommended pressures.
Speaking of real world. So many stop signs mean I never hit 40 kmh. Used SRAM calculator like he said and noticed immediate improvement on speed. 11 kmh to 20. I was running 38 PSI and the change to 70 PSI did wonders.
Were you running 12mm wide tires?😂
😂
Regarding the different results some people get between the Sram and Silca calculators, it's important to actually physically measure your mounted tyre width for the silca calculator!
You don't need to with the sram calculator as it takes into account the inner rim width!
I get nearly the same results from both calculators when i enter the details correctly! In the Sram i enter 32mm tyre width and 25mm internal rim width. In the Silca i enter 34mm as thats what my tyres measure at when fitted! If i enter them as 32mm (labeled width) the pressure recommendation goes up 6+psi.
For my tt bike with 25mm tyres and tubes, when i enter the details (these tyres measure at 25mm when fitted too) the results from both are about the same.
I've been running 50psi in 25mm tyres and I like it! 65kg. Sram calc. recommends 65-70! Obviously doesn't take Yorkshire roads into account!
It's funny, but I have no idea what tire pressure I run. I have a 40 year old Silca track pump, and the pressure gauge has been broken for a number of years. I've just been pumping up my tires and using my thumb to check the tire to see if it feels ok, and that's been working out very well for me. It's all about the feel. I'm old school 😆😁
same here, despite having latest tech bikes. old & new! :)
I had been using the Silca tire pressure calculator. With that calculator, I get a 16 PSI higher tire pressure than if I use the SRAM calculator with the same parameters. That's a lot!
same here lol
With the silca one, you need to input the actual measured tyre width when mounted, not what is written on it! And there's a lot more options on the road surface to select.
For example, in the stream calculator I enter 32mm tyres, 25mm internal rim, and road surface, and get pressures of 57.9 and 54.5
Using the silca calculator I select worn pavement/some cracks, 34mm (as this is what my tyres mounted measure at) and get 58.5 and 57. Pretty close! If I change my the width to 32mm (as written on the side) then the silca recommended pressures go up by 6psi!
So it's key with the silca calculator to measure the tyres width when fitted!
for tyre pressure calc go to the silca calculator since it even lets you choose more options for all the different surfaces.. not only wet or dry...
That calc puts me 20psi above the sram one. Both of them can’t be right…
As usual confusion reigns
Wow SRAM calc is saying I need 20psi less than I’ve been using. Can’t wait to try this out.
I just replaced a slow leaking tube that would drop from 55 psi to 35 psi over the span of about 5 days/rides. Personally, the rides at the beginning of the inflation cycle felt slightly easier on the legs but I can't detect subtle changes of effort because all I have is dumb MPH. I think I'm going to start out the new tube at 45 psi and see where that gets me.
With my TREK 6000 MTD i run my 26" x 2.25" Schwalbe tyres at 40 Psi, this gives me a good ride also avoiding any punctures 👍 Au
What would you suggest for me. I run 20" x 2.5" tyre at 100 psi. My rims are 42mm wide.
@@x88868 The tyre side wall says Max 50psi thats why i run at 40psi for tyre safety 🙏
Nice video, and glad you got the the 'how' part. For myself, I do it old school - based on the width of the tire, determining contact patch, and based on my weight. And as I am not pumping my tires up to some tenth of a pound, it is very fair. Also, not at all far off from the web based calculation.
What would be nice is if tyre manufacturers gave us info on what sort of tyre were using. Is it thin, standard, reinforced etc
SRAM changed the calculator it now lists standard, reinforced, and downhill, which is a little clearer than before.
Brompton's need 110 psi or your riding through treacle. Being a heavy rider I use 120 psi, I think pro's use 110, but they are lot lighter.
I always ride 32’s in the winter. Incredibly comfortable and added stability.
I'll get some too! What tire pressure do you go for?
@@nerdexproject I'm running 3.5bar on 32mm tire and it's perfect! I'm going for 35mm next time, hehe
Thanks for the answer man! :)
Does your fork allow for 35 mm? My road bike has an approximated inner fork width of 34 mm. (I measured it but it's a bit tricky...) I even hope that an inflated 32 mm tire won't expand more than 2 mm or I'm a bit screwed...😅
32 PSI? WOW….. MINE ARE 100 PSI
@@nerdexproject Yeah my fork allow 35mm in datasheets, so i could go a bit wider too. I think its not good idea to put 32mm tire to 34mm fork, you shou have +/-5mm reserve on each side. The wheel bends quite a lot while cornering :)
You're ruining my internet fun by providing such a nuanced and well explained video! I was so very ready to jump into the comments calling out nuances you missed. 🤣
Great work!
brilliant thanks very interesting will continue with my own tweeking on various bikes ....work bike needs lower pressure still for sure, road bike still lowering pressure gradually to get used to the feel... and hack bike is a cross bread so going to put wider tyres on that soon too, particularly for the wet conditions.... hard tail stays the same for now in case of snow or floods ha ha ha thanks again for the study..... sorry to here of the changes to GCN + will certainly continue to follow here, have indulged in new bib tights and jersey from your shop too hope the sales help keep the original idea afloat amid the new fangled streaming stuff ha ha ha thanks to your whole team enjoy your winter looking very gnarly ..Cheers Martin
Gonna come back in a year and see how many more videos GCN can manage on tyre pressures.
...and how many more products are placed in those videos.
Hey Michael, it’s a super important topic and we want to make sure that we’re creating videos for all cyclists not just the ones who’ve been watching GCN for a while. I’m afraid not every video can be relevant to every person, and if you already knew everything in this one hopefully there’ll be another video for you along soon. Cheers, Simon
Excellent reply to the snark!
Here's a thought. They're all titled. Seen enough to suit you? Don't watch more.
lower preasure means less chances for your inner tube to blow up. im 120kg and having high presure on a hot day is like asking for a road side replacement job :D
I ride 110 psi 😂 but then again, its a BMX.
I’ve always pumped mine up to where they deform enough to smooth out the crappy English roads but enough to corner hard and it’s usuall at least 20 psi than the max recommended.
You could hear the hurt and disappoinent (of the GCN+ cancellation) in Si's voice in his last sentence 😢.
We are extremely disappointed but you guys must be gutted...❤
I've been trying to get this across to people for over a decade. I typically had to order tires because the selection of 25 & 28mm performance tires were never in stock. I had to check my pressures right before heading to the line because I had a friend who would go behind my back and pump my tires to the max before races stating I was loosing watts.
85 kg. Co…tal - grandpix 5ooostr. Front 4bar/5.82. Rear 5bar/7.25 Total safety/comfort for mi. “ tubeles”😘
I have noticed that after after adopting this lowering tire pressure trend my body can take more cycling before feeling aches. But I have suffered a lot of sidewall tearing in many of my continental tires... You win some, lose some I guess.
I still cannot get used to lower pressures when you nail it out the saddle and you feel your tyre squishing it feels horrid. That's at 80 psi. I am a heavier rider. 120 psi for me
Jeez, how heavy are you?
@@richardmiddleton7770 86kg
100psi front, for 20s, 100 psi rear, for 23s.
Really great info. I, like I think many others, started off cycling with 120psi in the rear tire and 110 in the front. Those were some painful days. I had lowered that pressure quite a bit, but according to the calculator, not nearly enough. Really looking forward to setting them at the recommended pressures and seeing how it feels. I'm always up for a little more comfort and some added speed for free. Thanks for the really well done video Si.
I personally would not recommend that. Go at least 10 psi higher than the calculator. My rear inner tube got a 1/8" long split most probably because of bad contact with the rim when I had set it to the recommended pressure from that calculator. Got thrown over the bars on a 25mph downhill descent. Nothing wrong with the tire/rim or any sharp stuff stuck inside. This is just my experience and opinion. Never had such an incident when running higher pressures. (Or the manufacturer recommended pressures)
I think the calculator recommends pressures of 75 to 85 psi. I would recommend going at least 10 psi higher just to be safe.
@@padmanabhaprasannasimha5385 I've been running the recommended pressures for the past two rides and there is a notable difference in comfort on the bike. Really nice. I don't feel every little nook and cranny in the road as I did at the higher pressures. But to each their own, you have to do what makes you feel safe.
I just use 100psi (on my road-bike) and be done with it.
On my “cross-country”-type mountain-bike some local-bike-shops have put-in 40psi and some others have put-in 45psi and some-others have e put-in 50psi and some-others have put-in 60psi. Why the different variances? I dunno. But my tyres say “withstands up-to a MAXIMUM of 65psi” so i hypothesize that all-those-pressures that the local-bike-shops out-in are okay. (Also: the bike felt comfortable-to-ride with each of those pressures in the tyres, *AND*, i didn’t get impact-flats with any of those pressures).
Seems like off-road would be a more variable surface than on road.
Anyone else miss 18mm, 120psi blades? Either I’ve gotten slower or they were faster! 😮
I still think slimmer is faster! Faster climbing and accelerating anyway, because they're lighter. Now we have tubeless you can simply run skinnier tyres at lower pressures!
Jan Heini of Rene Herse (Compass) has done much more on this and srarted far earlier than Zipp.
Tubes 700x25 88- back 85-front. Tires measure 26mm
What's next: Stiff frames are making you slower!!😳🤔
For me it is suggest too low pressure, so the tier getting spoungy.
11 kg bike, 700x35c, 17 mm rim. Max load on the tier 6 bar. The calculator suggest just under 4 bar. I go for 5 bar.
Getting a strong Peters and Lee vibe from those shades, sir.
I’m disturbed to find Si saying lateral cornering pressures is so incredibly soothing. Anyway, back on the topic, SRAM is my go to calculator as well. I’m also nerdy enough to have a digital pressure gauge. I’d like to think I’m not obsessive just ensuring a nice ride
The digital gauge is not that nerdy after all. If you have an old school pump that goes up to 12 bar and you want to set your MTB tires to 1.6 and 1.8, it‘s almost impossible without it. One of my best gear buys.
29mm tire, thin good pavement - 5-5.3 bar- This works, however I have a question, why tire manufactures suggest higher pressure? even minimum more like 6 bar. You have Pirelli tires, look at the table on a box. Pirelli suggests >6 bar for that setup....
Love that paint!
Nice videos, nice trip. Can't wait to see the Moroccan episode . . .
Wish there was something like TyreWiz with +/-5PSI accuracy, for a sensible price. All I want to know is "have I lost more than 10PSI since I pumped up at the start of the ride?". Especially important on Tubeless setups.
I kept running the hookless recommendation of 60-65 PSI even after I switched back to hooked wheels on accident, lol Silca says I should be at 90 PSI -- we're gonna take that with a grain of salt.
Downtube shifta crew in da house.... Make it 23mil, make it rock hard🤨
This is one of the best tire pressure videos yet! Well done.
I find these sites are way low on their tire pressures. They give pinch flats way to easy with their settings.
They have different options if you are running tubes, or tubeless.
On my TT bike, with 25mm tyres and tubes they both suggest about 95psi. That's about the right mark. On my road bike with tubeless 32's they have me at 57 and 54. Down to 49 even in the wet.
My lbs lectured me for running too low pressure @70 psi. So he pumped my tire to triple digits. He exploded my latex inner tube. I'm 67 kg on a 28c.
Triple digits on 28's? wtf?
@@andrewmcalister3462 yep, but the "good news" was that he gave me a free butyl inner tube 😂
Time to find a new lbs
@@MrWobling but I just moved from the other lbs that told me my rear cassette needed new bearings 😂...but seriously I'm on my 3rd lbs and the latest crew seem really good
My tire have max pressure rating of 110 PSI. I pump it to 100 PSI and I got blown tube after 10km. Now I keep it at 80PSI.
Using the SRAM website and input all data correctly of my mtb i find that tyre pressure of 25 psi is recommended! Now thats way below what's stamped as minimum on my tyres 35 psi - thoughts GCN ?
After Si‘s musical performance in the latest GCN show, I was a bit disappointed that there is no Freddie Mercury reenactment in this video after seeing the title.
Silca calculator is best.
Whats your weight?
@@Goggles1 85 kg
It tells you 10-15psi to much imo
@malmsey1541 Not on clinchers. Of course it also could depend on how you measure your tire pressure. With my tires and pressure gauge it is pretty close to ideal. I usually go about 2 psi lower than what the calculator says. But is my digital gauge even accurate to +/- 2 psi? I have no idea. Certainly the ones on floor pumps aren't.
Tubeless 700x28 62 front 65 rear
I often wonder why it is not told that the Bicycle Rolling Resistance tests are done on an uneven surface that corresponds to natural conditions?? The result is that more pressure is faster on a normal surface??
excellent video as usual. I am going to keep my new road bike's 28mm tyres until they last long enough, but once they are done, I'm switching to 32mm tyres (the max my bike accepts). My two pump's gauges aren''t working well though, so I might have to buy something to read the pressure accurately.
A separate digital pressure gauge is really worth it. I use mine before every ride and also take it with me to races and set my pressure in the hotel room with a hand pump.
On my road bike I be 3412 but as often use 100psi on British roads
After Bohemian Rhapsody I guess a Queens’ fan as SI would have sung Under Pressure 😅
Sometimes it is mental. When I lower my wifes tires to 70 because she is 135 pounds on a 25 pound bike, she does the ride in 4 hours instead of 3. Pump back to 85 (max for her tires) she does 3 hours (same distance of course). My next move is drop to 70 and not tell her as a test lol.
Wow, another GCN video about tyre pressure. Looks like GCN are running out of steam.
From most of the comments here, the message still hasn’t sunk in; so many running 100+ psi on modern wide tires
Practical and useful advice. Thanks, Si.
I guess SRAM is a bigger sponsor than Silca.
Ooh yeah. The sponsorship deals on those free-to-use online calculators....
Wow! That was … comprehensive. And informative. Thanks!
Your Sram tyre pressure calculator has no TPU tubes option! Shame!
Well, I use TPU inners last 2 years and max pressure recommended is 75psi. That's it. I'm 125kg and I run TPU inners RideNow. Previously I had butyl inners and 115psi - nightmare. If I follow your calculator I should run 122psi. 😂😂. I do perfectly well with 75psi with no flats and no problems. It's perfect.
You guys should tell the people how different tyre setup works. Does matter if you run TPU, butyl, latex or tubeless. Another thing. Tyre pressure is changing with the speed, temperature, breaking (rims), loading etc. and varies during the ride. 2psi diffece for recreational ride is nothing.
I haven't found your video useful this time. I'm sorry.
By the way TPU inners are much better for road bikes. Cheaper, lighter and faster than the tubeless. 👍
I ran the calculator at 125kg, and to get a 122psi recommendation, I had to select 23mm tires on a 15mm rim - a very old school set-up. Nothing against old school set-ups, but it seems odd to run this with modern TPUs. I don't doubt your experience running 75psi without pinch flats, but am wondering if everything was entered into the calculator correctly?
@@andrewmcalister3462As per the RideNow TPU manual, the maximum pressure must be 75psi. It's not recommended to put more pressure than this. This is why I'm doing it and everything is perfect. The app recommended in the video above - Sram pressure calculator has NO TPU inner tubes option. Their calculations are for butyl or latex tubes only which doesn't make any sense. Driving on Lower pressure completely chenging the game as we know and all the other options, inclusive tubeless are useless for road bikes. I don't think tubeless is better for road bikes at all. The sealing is less and doesn't work as effective as with the MTB/gravels, but the mess is huge, it's expensive (wheels, tyres, valves, pumps, repair kit etc). TPU are 21-36g each and the repair kit is a self adhesive patch and a small alcohol wipe or 1g total. You need a basic pump and that's it.
I wonder why GCN and Sram don't promote the TPU tubes? May be they want us to spend more money for a premium gear?
Wow, a GCN presenter who has found a shadow-stand! 😂
#askgcntech What if the pressure on the calculator is always less than the lower pressure printed in my tyre?
Great video! Thanks :-) One question: How do I determine my tire casing value? I only have a TPI number.
Hi Si, I just purchased a new set of Zipp 303 Firecrest hookless rims for a Cervelo Soloist. Living in Colorado USA was looking for an all around wheelset (replacing Reserve 40/44 76/176 hub) primarily for paved road riding, on flats & rollers, with an occasional off road / hard packed dirt farm road. I plan on following Zipp’s compliance standards (Less than 73 psi, tires greater than 28mm, & following the hookless tire compatibility.
Question: 1) Following De Gendt’s crash and the UCI’s investigation into the safety of hookless; what has been your experience with riding & racing hookless tires on paved & hard pack dirt roads, any tires blowing off the rims. And 2) Could you rank the following tires 30mm: Sworks Turbo 2BR 2T/5T, Schwalbe Pro One TLE and GP 5000 AS TR. As a newbie to hookless rims I’m trying to determine if this is the right move.
Thanks for all you do
A little late now, but investigation showed that De Gendt was riding a 28 mm tyre when the minimum recommended was 30. That's almost certainly the reason for the bow out. I've had the same wheels for about a month and no problems even descending at speed down passes. Follow Zipp's recommendations for compatible tyre/pressure combinations.
If Simon ever decides to move on from GCN, he should definitely consider a career in Stand Up Comedy :)
Hi,Can we watch race highlights,racing news show,preview shows etc as usual on GCN Racing youtube channel even after closing GCN+...?
110psi on Pirelli P Zero….I weigh ~210lbs. SRAM says I should be running at ~90. I used to ride Conti’s. Their box recommends 110 for my weight. Who’s correct?
Give both a try and see which feels better/is faster?
@gcn Thanks, I have. 90psi feels squishy. As for speed, well, at 6' 5" & 210lbs, speed only happens on the downhills. ;-)
I thought I had my tyre pressures nicely dialed in but it turns out I was running at 60psi (40mm tyres on a touring bike) when I should have been running 40psi when fully loaded. Only 35psi when not touring with no luggage. Very surprising!! Thanks Si.
SILCA also has a good calculator.
I don't really care because I can google it, but I found no link to the tire pressure calculator in the description... unless it's very well hidden amongst the advertising links.
presenting while peddling. great scenes.
For those interested in more data points, Jan Heine’s ‘The All-Road Bike Revolution’ has more information on tire slip angle, and pneumatic trail.
My road bike with 32mm tubeless, 57 and 54 (pretty much the same results from both calculators). Sram recommends 53 and 49 in the wet. I'm wondering if i could run that all the time? I wanna run as low as i can without making me slower. Comfort is king for me!
On my TT bike i run about 90psi, which is a little under what both calculators recommend.
The calculated pressure is well below what pirelli recommends, about 1.5 bar difference for 26 mm, also using the silca tool results in higer pressure by 0.5 bar. So not sure what is optimal. HOWEVER, the 5.5 bar in 26 mm feels so soft compared to the 6.5 bar I usually run.
But Silva also describes how a slightly lower pressure affects losses only slightly, while being above the sweet spot increases mentioned losses comparably drastic. So I think being between the SRAM and Silva calculator is not a bad idea. :)
depends... I use calculator and go from there
I remember trying 120 psi with 20 mm tires, it wasn't very comfy.
@gcn how do i know if my tyre sidewall casing is "thin" or "standard" when using the SRAM pressure calculator?
Off topic, but, it’s really great canyon are sponsoring GCN and all and giving them all these flashy bikes, but it’s kinda annoying that after seeing all these cool colours, when I go on their website everything I’d be interested in seems to still be shades of beige 🤣
The tire has defective, the thickness of tire is varies from part to part. I'm 78kg weight with 25mm tubular, so I put it in the front 65 and the back 75 psi. This is 10 psi lower than the recommended air pressure of the slam.
I accept the science but what I'd like to know is how much actual difference does it make to the average cyclist in real world scenarios? For example, if the pressure calculator says I should run 75psi on my rear tyre but it's at 95psi exactly how slower will it be? Over a 30 mile ride is it minutes or just seconds?
It totally depends on the road surface. The rougher the surface the slower you would go, in the region of a couple of KPH potentially.
So where is the link to Sram tyre pressure calculator?
60psi front and rear on 700x30 Schwalbe pro one running tubeless, I weigh around 72/74 kg depending on when I weigh myself! Btw the roads where I ride are awful.
Does anyone happen to know of Conti GP5000 clincher and the S TR version are standard or reinforced? I'm not sure where to find this information. Thanks in advance.
You got one thing wrong. Air volume is what is holding up the weight. Therefore the more air in the tire the less pressure the air needs to be under to support a given weight.
Wrong. What's supporting the weight is the internal pressure (pounds per square inch) times the area of the contact patch (square inches). The resulting force, in pounds, is what is supporting the weight of the bike.
@@mikes1976 Now that is funny, Mike S. arguing with Mike S. lol. However, if you think that the entire volume of air is not contributing to holding up the weight then you are mistaken. Yes, the area of contact is the point at which the balancing force is concentrated. But every atom of atmosphere in the system is contributing to that balancing force. If the volume of the system is smaller then each atom has to contribute more force and therefore they need to be at a higher pressure.
Maximun allowed by the tyre.
Is it cynical of me to think these calculators are skewed to lower pressures to help sell Zipp's hookless rims? I looked at the white paper and it seemed biased to me. They didn't present data on new or good condition asphalt, and "rough" was not defined by anything more specific than rough.
Hey Greg, we asked Zipp this exact question and they pointed out that their tyre pressure research proceeded hookless. They made the move to hookless when they realised that high pressures weren’t needed.
I cant believe it took humankind until 2020s to figure out something this important and quite easily verifiable.
70-75psi
Pump them to max and go for it.
120 psi all dayyyy
It's very informative for people who race for instance. But for the majority of us it doesn't matter. On my summer bike I put 80 psi in the front and 85 in the back. On my hybrid winter bike I put 30 psi for off road and 40 psi for the road. No faffing about. People are whittling about too much technology, just get out and ride your bloody BIKE😊
Just checked SRAM's calculator. I ride Pirelli P Zero Race tubeless tires with the new Speedcore feature at 28mm. Would this tire be considered thin, standard or reinforced?
Reinforced is if got puncture belt I believe in tyre and thin be more if race tyre, I wrote down what they said but it's at home
Reinforced is if got puncture belt I believe in tyre and thin be more if race tyre, I wrote down what they said but it's at home
0:46 is the biggest pothole you could find?
Definitely the other side of Europe 😅
Am I correct in assuming that the calculator is for tubeless tires only? It doesn’t say that but the pressures Si is showing seem appropriate for tubeless but not tubed.
No. Both SRAM and Silca calculators take into account whether it's tubeless or tubed. They have options to select that.
The Sram one didn't have that option
Alex’s Hookless video is getting slammed. Alex is great, fantastic man. The message is “rubbish”
700x30. At 70psi
2:40 brother is flying, any idea of what speed is here?
This guy litteraly 3 years ago: "110psi and more is the most efficient pressure in tires"
Can I go below the pressure written on my sidewall??
Yes some brands like Schwalbe have recommended pressure range quite high. Usually I'm running tires around the lower limit but not too much lower, make sure it does not feel too soft when cornering.
Thanks!